Ultimate Large Rifle Primer Shoot-Out — 16 Types Tested
Click Photo to read full test results in Target Shooter Magazine.
Mother of All LR Primer Tests
If you shoot a .308 Win, or any cartridge that uses a Large Rifle (LR) primer, you should read an important article by Laurie Holland in Target Shooter Magazine. Holland, a talented shooter from the UK, tested no less than sixteen (16) different large primer types using a custom F-TR target rifle shot from the bench. Laurie loaded .308 Win ammo* with 16 LR primer varieties and then tested for average velocity, ES/SD, and group size. This may be the most comprehensive and thorough LR primer test ever done. Here are the primer types tested:
| 1. CBC Magtech 9½ 2. CCI 200 LR 3. CCI BR2 Match 4. CCI 250 Magnum 5. Federal 210 6. Federal 210M Match 7. Federal 215M Magnum Match 8. Fiocchi Large Rifle |
9. Kynoch Large Rifle 10. Murom KVB-7 (PMC LR) 11. Norma Superflash LR 12. PMC LR Magnum 13. Remington 9½ LR 14. Remington 9½ M Magnum 15. Sellier & Bellot LR 16. Winchester WLR |
LINK: READ Large Rifle Primer Test Complete (16 Primer Types)
Test Rig: Osprey Rifles-built F-TR rifle with Savage PTA action, 32″ Bartlein 1:12″-twist ‘Heavy Palma’ barrel, and Dolphin Gun Company modular stock with an F-Open/Benchrest fore-end.
Some of Laurie’s results may surprise you. For example, would you guess that Sellier & Bellot primers had the lowest ES, by a significant margin? And get this, among ALL the primers tested, Rem 9½M Magnum primers produced the lowest velocity, while Rem 9½ LR (non-magnum) primers yielded the highest velocity. (The total velocity spread for all primers was 35 fps). That’s counter-intuitive and it’s odd that Rems were at opposite ends of the speed spectrum among ALL primers tested.
“The rationale for doing side-by-side tests is to see what effect primer choice has on ballistics, i.e. average velocities and MV consistency. There are a great many views on the subject, a few based on tests (including primer flame photography) but most apparently hearsay.” — Laurie Holland
Every serious hand-loader should definitely read the full test results to understand Laurie’s methodology and get all the details. This is an important test, with significant findings. But if you can’t spare the time right now, here are some highlights below:
Primer with Lowest Velocity: Remington 9½ M Magnum (2780 fps)
Primer with Highest Velocity: Remington 9½ LR (2815 fps)
Primer with Lowest ES/SD: Sellier & Bellot LR (12/3.1 fps)
Primer with Highest ES/SD: Remington 9½ M Magnum (47/14.0 fps)
Primer with Smallest Group Size: Remington 9½ LR (0.43″ average, three 5-shot groups)
Primer with Biggest Group Size: CBC Magtech 9½ (0.7″ average, three 5-shot groups)
Editor’s Comment: Laurie shot three, 5-shot groups at 100 yards with each primer type. The average group size for the top six primers varied by only 0.10″ (0.43″ to 0.53″), so one can’t conclude that one type is much better than another. Total group size variance (from best to worst) was 0.27″.
“The biggest surprise to me … came from an elderly (at least 10 years) lot of Czech Sellier & Bellot standard caps with an ES of 12 and SD of 3.1 fps, way below those of the nearest competitor. By contrast to the Fiocchis, they were an almost slack fit in the cases and this may have contributed to their consistent performance.” — Laurie Holland
NOTE: Values in chart are based on 15-Shot strings. The ES/SD numbers will therefore be higher than is typical with five-shot strings.
All ES/SD Values from 15-Shot Strings
Testing 16 primer types was a huge task — we commend Laurie for his hard work and thoroughness. This extensive test is an important contribution to the “knowledge base” of precision shooting. Laurie’s findings will doubtless influence many hand-loaders who hope to produce more consistent ammunition, or achieve better accuracy. Credit should also be given to Target Shooter Magazine for publishing the results. Well done gentlemen…
*Reloading method for Test Ammo: “Test batches consisted of 16 or 17 rounds for each primer, charges thrown by an RCBS ChargeMaster and checked on lab-quality electronic scales, adjusted if necessary to within ± 0.04gn, so any charge weight variation would be under 0.1 grain which equates here to 5 fps.”
I’ve since rerun the series with .308 Win Palma brass and small primers. A write-up will be done soon. Results are much closer than with the LR primers and again there was a ‘surprise winner’ (CBC Magtech 7 1/2). Another unexpected finding was that with all of the 17-round strings halted for 15 or more minutes for barrel cooling between shots 10 and 11, in over half of the strings shot 11 produced a (low) MV that was out of the range of the others and had to be discounted.
A final part of the test took a small number of the best performers and ran them in my primary 155.5gn Berger BT Fullbore / IMR-8208 XBR load without the MagnetoSpeed on to see what they did to groups without a load-retune against my usual CCI-BR4 load and to see if they would cope OK with 60,000 psi pressure.
Use the .308 Win Palma brass and small primers myself. Very interesting. Thanks.
Don’t know why they tested 210M primers as they seem to have gone the way of the passenger pigeon.
I know everyone has a favorite, and although they’re really tough to get, I would really liked to see the Wolf LR-M in that mix.
The Murom KVB-7 or KVB-7M should be the Wolf LR-M under a different name. (Depends on whether the ‘M’ in the Wolf name is for Match or Magnum.) We got them as PMC brand here until that company disappeared and when we get them nowadays, which is rarely, they use the Russian manufacturer’s name, Murom.
I have never looked at primers apart from reliability. This another thing to consider in shooting.
Are Winchester primers still undersize?
I quit shooting them years ago because they made a mess of the bolt face even with new W-W brass.
Hi Laurie, your comment re S&B’s slack fit raises my question. How critical is the primer seating mechanism? Sometimes I hand seat with a Sinclair tool and sometimes I seat using the press. When I use the press the primers are seated harder.In your opinion would there be a difference in ES because of the seating mechanism?
Thank you,
Clive.
A good question Clive! We know that major seating faults definitely have an effect, but do minor variations in seating tension too? I suspect they have a minor influence, but that’s hunch not science! One (minor) reason that small primer brass may be better than many standard LR types is that it usually noticeably easier to seat SR primers and to get good ‘feel’ on their contacting the pocket floor.
Where are S&Bs sold without paying to special shipment?
Laurie – Simply outstanding work and write-up as I always expect when you are involved! Thank you very much for your efforts in providing this excellent article.
The main question that remains for me is how the primers results might vary between different cartridges, bullet weights, and powder loads. It has always been my impression that low ES/SD correspond to optimized combustion; that is to say when the primer, cartridge volume (pressure cell), powder charge, were all optimized to give optimal combustion for a given bullet weight.
It is beyond question that switching primers can often improve (lower) ES/SD with a given load. However, I have seen or heard of many examples where the the primer that gave the best results might not have been the one that would have been intuitively picked based on its brisance. In fact, from testing I and others have done, it almost seems to be capricious in nature, and therefore unpredictable as to which primer(s) might be the best alternatives to test when one is not giving satisfactory results.
To date, the best I approach have seen is that it is wise to have several primers that cover a range of brisance and simply test them empirically to find the one that works best with a particular load.
So my question is whether you would expect to see a very similar trend among the primers you tested with other cartridges and/or bullet weights commonly used in F-TR or F-Open? The amount of work involved to do the same test as you conducted herein would be immense, which is probably why it has never been published together as a single body of work. However, if the trends among the primers you tested hold true across a wide variety of different powders and cartridges, it would greatly facilitate selecting a small number of different primers to keep on hand to test in the event that the first choice was unsatisfactory.
On the other hand, if some of the primers that gave poorer results in your testing with a specific .308 load gave much better results with a different cartridge/powder/bullet weight, it would be much more difficult to make any general predictions that might allow a reloader to keep a stock of only two or three types on hand, one of which would be likely to give satisfactory results over a wide range of cartridges and powders. I guess what my question boils down to is whether you think the range of primer performance you observed in your test here would carry over to other cartridges and powder selections. Any thoughts? Thanks again for the excellent write-up and work!
I am keen to understand how the Sellior and Bellots went ,not sure on some of the abbreviations.Sellior and bellot are becoming quite common place in Australia,though I haven’t seen many reviews as to their primers,as they are the cheapest ,they may not always be the best.currently running up loads of Swede using 2209 and Sierra 123hpbt.